Lawnmower starts but won't continue to run

Have this checked IMMEDIATELY. The exhaust manifold is near the firewall in the engine compartment. The intake for the heater and ventilation / AC system is right above it. If you have a poor connection from the engine to the manifold OR the manifold to the exhaust pipe, you run the risk of carbon monoxide poisoning.

Motor issue

I am guessing that you have to prime it to start it. Is that correct? If so, then it starts on the prime and then dies right away. Then the next thing is whether or not the carburetor is mounted on the fuel tank or separately. If it is mounted on the tank, then you will need to replace the diaphram between the two. If the carburetor is mounted separately, then you will need to remove the carburetor to clean and inspect it. With this set up the float and needle are somehow stuck or you have a hole that is plugged.

I hope this is helpful for you.

The diaphragm between the carburettor and the fuel tank needs renewing.

You may want to check the intake manifold coolant port tube, which is plastic and tends to get eaten away over time on this particular engine. This condition causes coolant to mix with fuel in the intake manifold, making the engine run rough, and ultimately not start.

The replacement tube is metal, and will solve the problem. A good mechanic will insure the intake is clean and dry during re-assembly.

SOUNDS LIKE YOU NEED A FULE FLUSH AND CARB KIT

Remove the float bowl from the carburetor, clean it out and use a commercial spray carburetor cleaner to clean out the main jet in the center of the carburetor where the bowl nut screws in

i have the same problem on a 98 jimmy 4.3 4x4.
i replaced the fule pump and have good pressure.
new wiers & coil (good spark) no MIL & no codes.
will only start when primed. it will run & drive all day
with no problems.
but once it has been turned off (warm or cold) i will
have to prime it once again to start it.
i have another engine that was in it before it spun a bearing.
it ran fine so i know all parts are good.
i swaped the mass air flow and throttle body but i still have
to prime it everytime to start it. am i forgetting something?
should i swap out the intake with the injectors?
any help would be sweet. thanks.

Check for a intake hose leak between your mass air flow sensor and the intake manifold. Porsche refers to this piece as a vane air flow sensor.

It is the head gasket. Have that replaced and you will be fine. You have an air leak. I was told by the mechanic at mazda that the anti freeze eats away at the gaskets. CRAZY, but it works. I still have an issue with my 2001 Tribute revving while in park. Its always something.